Retromod

Create a polyfill provider that re-implements a removed API so old mods still work. Use when mods crash with ClassNotFoundException or NoSuchMethodError for completely removed classes.

Create a new version shim to add support for transforming mods between two Minecraft versions. Use when adding support for a new MC version or filling gaps in the shim chain.

Debug a Minecraft crash caused by a mod that Retromod transformed. Use when a mod crashes after transformation and you need to find and fix the root cause.

Work with Minecraft name mappings: intermediary, Mojang official, SRG, and Yarn. Use when adding new mappings to IntermediaryToMojangMapper, generating mapping files with MappingComposer, or debugging name mismatches.

Work on mod loader compatibility for Fabric, NeoForge, Forge runtime integration, version constraint relaxation, and mod metadata patching. Use when fixing mod loading issues, version rejection errors, or adding support for a new loader version.

Search, download, and work with mods from Modrinth. Use when downloading test mods, checking mod compatibility, or finding mods for a specific MC version and loader.

Test that Retromod correctly transforms mods for a target Minecraft version. Use when verifying transforms work, testing new shims, or debugging mod compatibility.

Build Retromod from source and deploy it to a Minecraft installation for testing. Use when you need to rebuild after code changes and test in-game.